I am trying to configure the comms between two SLC 5/04's with rack mounted KE modules over a leased line modem link.

On both, The SLC comm 0 is configured for DH485 with the required NET-AIC and AIC to link to the KE module.

Each KE is setup for DF1 full duplex protocol with the PLC processor and KE module DH485 addresses reversed at each end.

I have connected two 9 to 25 way modem cables together to try and at least establish comms that way before introducing further complexity of modems.

I have tried varias KE settings but cannot even get the DF1 LED on!!!

Any comments would be greatly appreciated.

Thanks

Pete

 

Pete, As far as I know the 1747-KE module port can only act as a slave. In the past, I have done similar projects but have always used a SLC or PLC as a master talking to or reading from the KE. Have used 2 wire leased lines with Multitect MT202D 1200 baud modems between SLCs and PLCs. email me for more info . Good luck.......

 

Pete,
Are you using a null modem cable when connecting the PLCs directly together? If the DB9-DB25 cables are designed to work with modems, then you must use a null modem cable between them when connecting direct.

The pinout of a null modem cable with DB25s is:

2-----3
3-----2
4-
|---8
5-
-4
8---|
-5
7-----7
6-----20
20----6

Good luck,
Jim Ralston

 

Pete,

> I have connected two 9 to 25 way modem cables together to try
> and at least establish comms that way before introducing further
> complexity of modems.

Try a modem eliminator cable. The modem eliminator will cross the RX and TX lines (as well as other "control" lines if your using them).
If you just connect two modem cables this reversal will not occur.

Jerry

------------------------------------------------------------
Jerry M Baucum
Bullet Software
3213 Peppertree Pl.
Plano, TX 75074, USA
Tel: (972) 633-9111
Fax: (972) 633-9112
Email: [email protected]
Web: www.bulletsw.com

 

Pete---

There are issues with modern modems that complicate DF1 connections, but I have to start by wondering why your system is so complicated already.

You can talk through modems and a leased line directly from a SLC CH0 to another SLC CH0 without using DH485 at all. Meanwhile, although a 5/04 and a KE can do some interesting things, I'm not sure that your application needs the Remote
Messaging technology when you could simply exchange messages between the two nodes. (I suspect your DF1 LED is dark because neither existing node is trying to send a remote message!)

Do you need DH485 at either end? If not, then put the leased line modems on the CH0s directly, verify your port settings under System Mode/DF1 Full Duplex at each end and on the modems (9600 baud or lower), and try sending some LOCAL messages from one 5/04 to the other.

Hope this helps!

Larry Lawver
Rexel / Consolidated / Central Florida